The 49-year-old, who is the daughter of an Irish immigrant, is said to be joining America First Policies, a PAC that works to support President Trump's agenda and who is believed to have been actively pursuing her. A report from the HuffPost claims the departure from 12-year tenure FOX News was involuntary.

The presenter's departure effective immediately and she did not appear on Friday's "The Five" to say farewell, with contributor Katie Pavlich hosting in her place. Her absence went unmentioned.

The New York Times reports that as Guilfoyle was considered a pundit over a news reporter, she was previously allowed to keep her role on "The Five" despite her relationship with the First Son as long as she disclosed the connection on air if the Trump Organization was referenced.

Guilfoyle had already joined Trump Jr. as he stumped for Republican Senate candidate Matt Rosendale in Montana.

Sources familiar with plan tell me Kimberly Guilfoyle expected to take a role with America First - super PAC that supports Trump agenda https://t.co/NHE5Abrhd5

"Just as everyone else thanks to their significant others, I got to thank Kimberly for coming out here. We're going to take her fishing tomorrow, then shooting," he told the crowd, according to Vanity Fair.

"This is a miniature test to see if she really likes it, or if she's going to pretend to like it, but either way we're going to have a good time — or at least I will."

After the departure of Irish American Sean Spicer as Trump's White House Press Secretary last year, it was rumored that the President was considering Guilfoyle for a role on his communications team.

She also spent July 4 in the White House, meeting with her prospective future father-in-law.

Twice divorced Guilfoyle had been linked to Don Jr., 40, for several weeks following from the eldest First Son’s split from his wife in March 2018. While the pair was spotted together following President Trump’s State of the Union address in January 2018, which Guilfoyle was covering for Fox, the relationship is believed to have started after Don’s estranged wife Vanessa filed for divorce. Since the split, it has been revealed that Don Jr had an affair with Aubrey O’Day.

He and Vanessa split this year after 13 years of marriage. The couple has five children together; Kai (10), Donald III (9), Tristan (7), Spencer (5) and Chloe (3).

Guilfoyle also has an 11-year-old son named Ronan from her second marriage to Eric Villency, the CEO of a design firm. She was also previously married to Gavin Newsom, a Democrat and California’s Lieutenant Governor.

Her father Tony Guilfoyle immigrated to the US from Ennis, Co. Clare in his 20s and Guilfoyle returned there every summer, working in her family’s local store, and even staying in Ireland to study law in Trinity College Dublin. Before joining Fox in 2006, Guilfoyle worked as a prosecutor in San Francisco, then as deputy district attorney in Los Angeles.

“I grew up partly in Ireland,” Guilfoyle said.

“Every summer from the age of five, I lived in Ennis where my Guilfoyle relatives had businesses on O’Connell Street — a gift shop called Dalcassian House, and Dalcassian Printers. I worked in the shop, which sold lovely china and Waterford Crystal.

“I was about 11 or 12 and I got about IR£10 a week. It instilled a sense of responsibility in me, putting in the hours and earning the money.

“My late father Anthony Guilfoyle left Ireland in his twenties and went to work in America. He worked in construction in San Francisco and later became a contractor and political adviser. He was drafted into the US Army and stationed in West Germany. My mother, Mercedes, was a special needs teacher who died when I was a child. My parents worked hard to ensure we had a better life. They supported us and gave us the courage to pursue our dreams. I appreciate that greatly. My father was so proud of my achievements.”

Kimberly Guilfoyle attends the 'Acrimony' New York Premiere on March 27, 2018, in New York City.Jamie McCarthy/Getty Images